UTSA-74: a metal organic framework with two accessible binding sites per metal center for gas separation and gas storage

Abstract

A metal-organic framework (MOF) and uses thereof are provided herein, including an MOF comprising a repeat unit of the formula [Zn 2 (H 2 O)L.0.5H 2 O] n , wherein L is a ligand of the formula: The MOFs provided herein may be used in the separation of two or more gaseous molecules from each other. In some embodiments, the gaseous molecules are carbon dioxide and acetylene.

What is claimed is: 
     
       1. A metal-organic framework comprising a repeating unit of the formula: [M 2 L] n , wherein: M is a divalent metal ion and L is a ligand of the formula: 
       
         
           
           
               
               
           
         
       
       comprising a rhombohedral unit cell of a: 22.9 ű5%, b: 22.9 ű5%, and c: 15.9 ű5%; or a hydrate thereof. 
     
     
       2. The metal-organic framework of  claim 1  comprising a repeating unit of the formula: [M 2 L] n , wherein: M is a divalent metal ion and L is a ligand of the formula: 
       
         
           
           
               
               
           
         
       
       comprising a rhombohedral unit cell of a: 22.8 to 23.0 Å, b: 22.8 to 23.0 Å, and c: 15.8 to 16.0 Å; or a hydrate thereof. 
     
     
       3. The metal-organic framework of  claim 1 , wherein M is Zn 2+ . 
     
     
       4. The metal-organic framework of  claim 1 , wherein the metal-organic framework comprises a powder X-ray diffraction spectrum having a peak at 7.709° 2θ using CuKα radiation. 
     
     
       5. The metal-organic framework of  claim 4 , wherein the powder X-ray diffraction spectrum further comprises peaks at 14.262 and 15.454° 2θ. 
     
     
       6. The metal-organic framework of  claim 5 , wherein the powder X-ray diffraction pattern further comprises peaks at 7.117, 10.5, 11.981, 13.039, 13.373, 14.262, 15.454, 16.232, 16.711, 17.032, 18.427, 18.719, 19.599, 20.271, 20.49, 21.089, 21.464, 22.484, 22.794, 22.837, 23.076, 23.27, 24.096, 24.363, 25.054, 25.59, 26.25, 26.556, 26.933, 27.398, 27.656, 27.892, 28.055, 28.752, 28.787, 29.468, 29.57, 29.811, and 30.031° 2θ. 
     
     
       7. The metal-organic framework of  claim 1 , wherein the rhombohedral unit cell is 22.917, 22.917, and 15.902; 22.956, 22.956, and 15.883; or 22.951, 22.951, and 15.897. 
     
     
       8. The metal-organic framework of  claim 1 , wherein the metal-organic framework is a hydrate. 
     
     
       9. The metal-organic framework of  claim 8 , wherein the metal-organic framework is a hemihydrate. 
     
     
       10. The metal-organic framework of  claim 1 , wherein the metal-organic framework further comprises a water molecule in each repeating unit. 
     
     
       11. A method of separating two or more compounds using a metal organic framework comprising:
 (A) obtaining a metal-organic framework of  claim 1 ; 
 (B) combining the metal-organic framework with a mixture comprising a first compound and one or more second compounds; and 
 (C) separating the first compound from the one or more second compounds based upon their differential sorption rate within the metal-organic framework. 
 
     
     
       12. The method of  claim 11 , wherein the first compound is acetylene. 
     
     
       13. The method of  claim 11 , wherein the second compound is carbon dioxide.